{
\def\sym#1{\ifmmode^{#1}\else\(^{#1}\)\fi}
\begin{tabular}{l*{6}{c}}
\hline\hline
            &\multicolumn{1}{c}{(1)}&\multicolumn{1}{c}{(2)}&\multicolumn{1}{c}{(3)}&\multicolumn{1}{c}{(4)}&\multicolumn{1}{c}{(5)}&\multicolumn{1}{c}{(6)}\\
            &\multicolumn{1}{c}{dempdens53}&\multicolumn{1}{c}{dempdens53}&\multicolumn{1}{c}{dempdens53}&\multicolumn{1}{c}{dempdens53}&\multicolumn{1}{c}{dempdens53}&\multicolumn{1}{c}{dempdens53}\\
\hline
dempdens45  &     -0.7501\sym{a}&     -0.8269\sym{a}&     -0.8463\sym{a}&     -0.8937\sym{a}&     -0.9039\sym{a}&     -0.9285\sym{a}\\
            &    (0.0363)       &    (0.0461)       &    (0.0462)       &    (0.0577)       &    (0.0543)       &    (0.0424)       \\
\hline
\(N\)       &         174       &         174       &         174       &         174       &         174       &         158       \\
\(R^{2}\)   &       0.757       &       0.800       &       0.793       &       0.839       &       0.844       &       0.883       \\
\hline\hline
\multicolumn{7}{l}{\footnotesize Standard errors in parentheses}\\
\multicolumn{7}{l}{\footnotesize \sym{c} \(p<0.1\), \sym{b} \(p<0.05\), \sym{a} \(p<0.01\)}\\
\end{tabular}
}
